Håøya is an island in Porsgrunn Municipality in Telemark county, Norway. The 2.4 km2 island is located in the Langesundsfjorden, about 5 km east of the town of Langesund (in Bamble Municipality). About 1.8 km2 of the island (most of the island) is protected as a nature reserve. Håøya nature reserve was established in 2002 to preserve a coastal landscape with a large variety of little affected forest types, including the southernmost natural beech forest in the country. Historically, the island had permanent residents and its own school. Today, there are no permanent residents, but there are many holiday cottages for vacationers. The island is known for having summer camps arranged by Oluf Reed-Olsen.